Figure 11-3 illustrates a typical charging/starting system/in quasi-realistic style. The next drawing (Fig. 11-4) is a true schematic of the same system, encoded in a way that conveys the maximum amount of information per square inch.

Neither of these drawings is to scale and the routing of wires has been simplified. The technician needs to know where wires terminate, not what particular routes they take to get there. When routing does become a factor, as in the case of electronic engine control circuitry, the manufacturer should provide the necessary drawings.